Nihilism carries plenty of hope; it carries the hope that the values we make for ourselves

Not inherently. What you’re describing is nihilistic optimism, that’s the thing that I subscribe to, and you’re pretending that it’s the only kind that exists.

I do not get this “nihilism means you feel everything is hopeless” notion,

There are people who want it to be this way. Grifters and pessimists.

I cannot simply decide that idea is factually wrong simply because I didn’t want it to be true,

You can, actually.

There are no facts to speak of here. You’re bringing facts over the is-ought gap. If meaning cannot come from the universe itself, then you socially construct the universe you want to live in.

The universe that I choose to live in is a hopeful one. The universe that 4chan nazis choose to live in is a suicidal one.